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Female‐biased sexual size dimorphism stands as a widespread evolutionary pattern. Fecundity selection, favouring larger females with greater reproductive output, is a leading explanation. However, larger body sizes demand greater energy intake, potentially hindering the evolution of extreme female sizes. Thus, the evolution of more lucrative foraging tactics may allow for an increase in size. Hence, coupled with selection against larger males, fecundity selection should result in larger SSD in species with more lucrative foraging strategies. Crab spiders are sit‐and‐wait predators that hunt in several plant substrata. Species that forage on flowers or employ prey‐luring strategies likely have access to higher food intake than other species. We extracted body size measurements of 614 crab spider species from 43 genera and classified them based on their foraging strategy. Our findings show that foraging strategies that provide higher energy input (EFS) result in larger SSD. Statistical estimates indicate that females have a cephalothorax width 91% larger than males in EFS species, compared to 26% larger females than males in non‐EFS species. These differences possibly arise due to larger females and smaller males. The effects on male size reduction might result from scramble competition, whereas the increase in female size is likely due to fecundity selection. These results suggest that the shift towards more lucrative foraging strategies may have been a key event in body size and SSD evolution in crab spiders. [ABSTRACT FROM AUTHOR]

Many studies have explored the potential of companion plants to manage pests through top–down or bottom–up effects in agricultural fields. Buckwheat is known as a good candidate for companion planting with various crops to enhance pest management, but rarely in soybeans.We investigated the impact of planting buckwheat as a new companion plant on the population dynamics of major soybean pests and their natural enemies in soybean fields in Andong, Republic of Korea. We recorded numbers of pests and natural enemies at 9–10‐day intervals from 20 soybean plants each in eight small experimental fields throughout the cropping season.Significant reduction in pests, such as Riptortus pedestris (F.) (Hemiptera: Alydidae) adults, and a significant increase in natural enemies, such as Orius species (Hemiptera: Anthocoridae) and crab spiders (Araneae: Thomisidae), were observed in the buckwheat treatment plots. However, there were significant increases in other pests, such as leafminers and leafhoppers, in the buckwheat treatment plots. While we observed effects on R. pedestris adult density, we did not find significant effects on other developmental stages of this pest or its parasitoids.Although there were some concerns in the buckwheat treatment plots, the positive effects of buckwheat in soybean fields appear to outweigh the drawbacks. Buckwheat is likely a suitable companion plant for use in soybeans to manage pests. [ABSTRACT FROM AUTHOR]

Predation exerts a profound influence on the evolution of camouflage and detection abilities in both predators and prey. For instance, flower‐visiting spiders need to ensure their concealment when ambushing on flowers, which compels pollinators to check any spider cues cautiously before landing. Although numerous studies have examined the visual camouflage of spiders deceiving bees, little is known regarding whether spiders also employ olfactory camouflage. Additionally, the detection of spiders by dipteran insects is often overlooked, despite them being major non‐bee pollinators. Here, we explored the detection ability of dipteran pollinators and the crypsis skill of spiders from both olfactory and vision perspectives using the housefly Musca domestica L. (Diptera: Muscidae) as prey, the crab spider Ebrechtella tricuspidata (Fabricius) (Araneae: Thomisidae) as predators and chamomile Matricaria recutita L. (Asteraceae) as substrates. Our olfactory experiments revealed that experienced houseflies could respond to and avoid spider odour. However, this response did not appear to be innate, as naive individuals showed no aversion. Moreover, experienced houseflies did not have any avoidance behaviours to the mixed odours of spider and flower, indicating that spiders achieved olfactory crypsis utilizing floral scent. Our vision experiments and visual modelling demonstrated that houseflies could detect spiders positioned on flower. Surprisingly, instead of avoiding them, houseflies exhibited a preference for flowers occupied by female spiders, suggesting the attractive nature of female spider colouration. This paper provides evidence for the first time that crab spiders use floral scent to achieve olfactory crypsis and proposes a potential yellow‐signalling mechanism for crab spiders to attract insects. [ABSTRACT FROM AUTHOR]

The species Xysticus lendli is known only from its original description of a single male and one doubtful record so far. Here, we illustrate and redescribe the species based on 34 specimens in total and describe its female for the first time. We illustrated the male palp via compound micrographs and scanning electron micrographs. We generated a DNA barcode and placed it into a current phylogenetic scaffold to confirm the species' placement of Spiracme, a long-debated sister- or subgroup of Xysticus; hence, a new combination of Spiracme lendli (Kulczyński, 1897), comb. nov. is proposed. We illustrated the visually similar Xysticus mongolicus and the type species of Spiracme, S. striatipes, and compared them to S. lendli to aid future distinctions between those species. [ABSTRACT FROM AUTHOR]

Changes in leaf phenology from warming spring and autumn temperatures have lengthened the temperate zone growing "green" season and breeding window for migratory birds in North America. However, the fitness benefits of an extended breeding season will depend, in part, on whether species have sufficient dietary flexibility to accommodate seasonal changes in prey availability. We used fecal DNA metabarcoding to test the hypothesis that seasonal changes in the diets of the insectivorous, migratory black‐throated blue warbler (Setophaga caerulescens) track changes in the availability of arthropod prey at the Hubbard Brook Experimental Forest, New Hampshire, USA. We examined changes across the breeding season and along an elevation gradient encompassing a 2‐week difference in green season length. From 98 fecal samples, we identified 395 taxa from 17 arthropod orders; 242 were identified to species, with Cecrita guttivitta (saddled prominent moth), Theridion frondeum (eastern long‐legged cobweaver), and Philodromus rufus (white‐striped running crab spider) occurring at the highest frequency. We found significant differences in diet composition between survey periods and weak differences among elevation zones. Variance in diet composition was highest late in the season, and diet richness and diversity were highest early in the season. Diet composition was associated with changes in prey availability surveyed over the green season. However, several taxa occurred in diets more or less than expected relative to their frequency of occurrence from survey data, suggesting that prey selection or avoidance sometimes accompanies opportunistic foraging. This study demonstrates that black‐throated blue warblers exhibit diet flexibility and track seasonal changes in prey availability, which has implications for migratory bird responses to climate‐induced changes in insect communities with longer green seasons. [ABSTRACT FROM AUTHOR]

Since its introduction into Seattle, King County, Washington, prior to 1952, the European thomisid Ozyptila praticola (C. L. Koch, 1837) has spread throughout the eastern Puget Lowlands to inhabit an area of over 1300 sq mi (3400 sq km) centered in western King and Snohomish Counties. A separate population of O. praticola was also found in western Whatcom Co. that may be linked to the O. praticola population in Metro Vancouver, British Columbia, Canada. Ozyptila praticola was eudominant (> 10% abundance) in 86% of fallen conifer cone, 69% of moss, and 55% of litter samples. It was largely found in anthropogenically disturbed habitats, with some invasion into forests adjacent to development. Females, penultimates, and a consistent size-range of pre-penultimate juveniles were present year-round. Males were found mainly in spring and fall. Ozyptila praticola may be expected to continue increasing its range in anthropogenic and adjacent habitats in western Washington. [ABSTRACT FROM AUTHOR]

We present new records and species of running crab spiders (family Philodromidae) from Colombia representing four genera: Apollophanes O. Pickard-Cambridge, 1898, GephyrellulaStrand, 1932, PetrichusSimon, 1886, and Tibelloides Mello-Leitão, 1939. The genus Gephyrellula is recorded based on the newly described G. lavidabonitasp. nov., known from females from the department of Magdalena, constituting the northernmost known locality for the genus, at Sierra Nevada de Santa Marta. This new species can be differentiated from the (previously monotypic) type species G. violacea (Mello-Leitão, 1918), known from southeastern region of Brazil, by the longer than wide epiginal plates (wider than long in G. violacea), with narrower and shorter ducts of the glandular heads (thicker and longer in G. violacea), and by their more posteriorly placed fertilization ducts. The genus Apollophanes is here firstly recorded from males and females of A. punctipes (O. Pickard-Cambridge, 1891) from the Atlántico, Magdalena, Cesar, Cundinamarca, and Boyacá departments. Tibelloides is recorded from males and females of T. bryantae (Gertsch, 1933), from the departments of Magdalena and Meta, also representing northernmost known localities for the genus. Finally, new faunistic and taxonomic data is presented for Petrichus. Our examination of the holotype of Thanatus granadensisKeyserling, 1880 demonstrates this species is conspecific with more recently collected and better-preserved specimens of Petrichus griseusBerland, 1913, from the department of Santander. Therefore, we propose the new combination Petrichus granadensiscomb. nov., regard P. griseus as its junior synonym syn. nov., and update knowledge of its distribution. [ABSTRACT FROM AUTHOR]

In Italy, the selenopid spider Selenops radiatus Latreille, 1819, was hitherto only known from the Aeolian Archipelago (northeastern Sicily), with a record from the island of Alicudi and plausible sightings from the island of Filicudi. In this paper, we present twentysix new records from Sicily sensu stricto and its satellite islands, consisting of observations gathered from online naturalist networks and one adult specimen collected from the area where most observations were made. Nearly all records were made in buildings or similar artificial habitats, supporting the hypothesis that occurrences of S. radiatus are mainly limited to synanthropic environments in Sicily. [ABSTRACT FROM AUTHOR]

• Drip irrigation is currently the main solution adopted by winegrowers to cope with climate change in Mediterranean vineyards. • Evidence of the ecological impact is still scarce. • Irrigation reduced entomophilous flower cover in vineyard inter-rows. • Irrigation negatively affected beneficial arthropods. • Irrigation reduced the diurnal predation. Over the last decades, the use of irrigation in vineyards has grown exponentially in response to climate change. In the Mediterranean region, irrigation is the most widely used method of preventing water stress and high sugar content in grapes. However, little is known about potential irrigation effects on biodiversity. This study aims to understand the effect of irrigation on inter-row vegetation, on the abundance of beneficial arthropods and on the predation of pest insects. In the Luberon region of South-Eastern France, nine irrigated and nine non-irrigated vineyards were analysed. Drip irrigation was applied only during the two driest months of the growing season. We found lower flower cover in irrigated vineyards but no difference in species richness and total vegetation cover. Similarly, abundances of several beneficial arthropods were directly affected by irrigation, such as crab spiders, ladybirds, ladybird larvae and parasitic wasps. Structural equation modelling (SEM) revealed that negative irrigation effects on these arthropods were mediated by negative effects on flower cover. Predation rates were also lower in irrigated vineyards but only during daytime. Grapevine yield was not affected by irrigation. Experiments manipulating water availability under controlled conditions may help to understand this surprisingly strong effect of irrigation on flower cover and beneficial arthropod abundance. [ABSTRACT FROM AUTHOR]

The meadow spittlebug Philaenus spumarius L. (Hemiptera: Aphrophoridae) is a xylem‐sap feeder and the most abundant and widespread vector of Xylella fastidiosa (Xanthomonadales: Xanthomonadaceae) throughout Europe. Control strategies for the disease are based on containment and eradication measures regulated by the European Union. Within the context of biological control, the use of natural enemies aims at limiting the insect vector population in agroecosystems. Spiders are generalist predators with potential as biological control agents occupying all the habitats within crops. Crab spiders (Thomisidae) could be potential natural enemies against P. spumarius. The functional response (FR) of a predator represents the intake rate as a function of food availability and allows estimating feeding behaviour parameters such as the prey handling time and attack rate. However, spiders often kill more prey than they consume, unveiling their capacity as natural enemies. We assessed and compared the FR of Xysticus acerbus (Thomisidae) fed on P. spumarius in the laboratory considering (1) the total number of dead individuals and (2) only the consumed ones. We found that although both FRs were of type‐II, they significantly differed. The values of attack rate and handling time for consumed were 0.1 and 3.6, respectively, while for dead, the attack rate was 0.3 and 1.1, being both significantly different. Moreover, the number of overkilled individuals reached a plateau at the highest prey densities. Xysticus acerbus could be a potential natural enemy of P. spumarius. Nevertheless, we suggest that the effect of including the killed but not consumed prey individuals in FR studies using wasteful killing predators should be considered and further studied. [ABSTRACT FROM AUTHOR]

Ecological restoration often targets plant community recovery, but restoration success may depend on the recovery of a complex web of biotic interactions to maintain biodiversity and promote ecosystem services. Specifically, management that drives resource availability, such as seeding richness and provenance, may alter species interactions across multiple trophic levels. Using experimentally seeded prairies, we examine three key groups—plants, pollinators and goldenrod crab spiders (Misumena vatia, predators of pollinators)—to understand the effects of species richness and admixture seed sourcing of restoration seed mixtures on multitrophic interactions.Working with prairie plants, we experimentally manipulated seed mix richness and the number of seed source regions (single‐source region or admixture seed sourcing). In each experimental prairie, we surveyed floral abundance and richness, pollinator visitation and plant–M. vatia interactions.A high richness seed mix increased floral abundance when seeds were sourced from a single geographic region, and floral abundance strongly increased pollinator visitation, M. vatia abundance and prey capture. Seeding richness and admixture seed sourcing of the seed mixture did not affect floral species richness, but floral species richness increased pollinator visitation.Pollinators interacted with different floral communities across seeding treatments, indicating a shift in visited floral species with restoration practices.Synthesis and applications. Long‐term success in prairie restoration requires the restoration of plant–arthropod interactions. We provide evidence that seed mix richness and admixture seed sourcing affect arthropod floral associations, but effective restoration of plant–arthropod interactions should consider total floral resource availability. Incorporating a food web perspective in restoration will strengthen approaches to whole ecosystem restoration. [ABSTRACT FROM AUTHOR]

Xysticus cristatus is a Palearctic species, very abundant in the north-western Himalayas having a temperate climate. It is one of the predominant species in the agroecosystems of Kashmir. For a period of two years, we conducted a study on the population of Xysticus cristatus inhabiting the agroecosystems of Kashmir. A phenological study was conducted under field and laboratory conditions and temperature, rainfall, and humidity were monitored as indicators of population size. The spiders appear to have an annual reproductive cycle and a spring–summer stenochronous phenological pattern. Adult spiders emerge in spring, recruitment of spiders occurs in summer, they undergo overwintering in the immature stage and all stages of development show sequential phenological maxima. Under laboratory conditions, almost all spiders took VII instars to develop, and considerable variations were observed among all the instars. The abundance of Xysticus cristatus did not show any correlation with climatic variables at time 0, although there was a correlation with temporal lag. The best-adjusted correlation was found with a 3 month time lag, indicating that species require time to respond to changes in the environment. [ABSTRACT FROM AUTHOR]

Taxonomic notes on the Talaus species from China are provided. Two new species, T. yuyang Yao & Liu, sp. nov. and T. zhangjiangkou Yao & Liu, sp. nov. are described and illustrated, and a further three species are redescribed based on their genitalic characters: T. dulongjiang Tang, Yin, Ubick & Peng, 2008, T. niger Tang, Yin, Ubick & Peng, 2008, and T. sulcus Tang & Li, 2010. The species T. xiphosus Zhu & Ono, 2007 is considered a junior synonym of T. triangulifer Simon, 1886 based on an examination of many recently collected female and male specimens from Guangxi Province, China. Diagnoses, detailed illustrations and a map of distributional records of the six treated species of Talaus in China are provided. [ABSTRACT FROM AUTHOR]

The camouflage of crab spiders on flowers have been extensively studied, primarily focusing on species with uniform coloration. In reality, more than 50 flower-visiting spider species from seven families do not possess uniform coloration. However, there is a lack of exploration regarding them, leaving their cryptic nature uncertain. Additionally, little is known about the flower-visiting strategies employed by spiders at different developmental stages. To address these issues, we investigated Ebrechtella tricuspidata, a crab spider species exhibiting distinct abdomen and carapace colors. Notably, during our earlier field survey, we found that the juvenile spiders appeared on chamomile flowers (Matricaria recutita) significantly more frequently compared to the females. Our visual modeling showed that the spider's carapace on flower petals was detectable, whereas the abdomen matched the flower petals in both chromatic and achromatic contrast, making it unlikely to be detected by avian. Our predation experiment revealed that the probability of being detected and attacked was significantly lower for spiders on flower petals. Moreover, the attacked percentage of juveniles on petals was significantly lower than that of females. Combined with our previous field findings, we predict that spiders in different developmental stages may employ different flower-visiting strategies according to their predation risk. Overall, our study demonstrated that imperfect crypsis of E. tricuspidata on flower prevents avian predation effectively, and the higher presence of juvenile spiders on flowers may be attributed to their lower predation risk. Significance statement: Crab spiders are renowned sit-and-wait predators and provide an ideal model for studying animal camouflage. It is widely acknowledged that these spiders exploit flowers of matching hues to deceive their prey. However, there is a pressing need for broader investigations encompassing the camouflage of crab spiders with non-uniform body colors to predators and their flower visiting strategies during ontogeny. To investigate these questions, we conducted avian visual modeling and behavioral experiments. Our findings demonstrated that distinct local body part did not significantly impact overall concealment, suggesting that camouflage is prevalent not only among flower-visiting spiders sporting uniform coloration but also among those with different colored abdomen and carapace. Furthermore, juvenile spiders on flower experienced lower predation risk than females, indicating that spiders at different stages face distinct levels of predation risk. Combined with our previous field findings that juvenile spiders were significantly more commonly found on flowers than females, we predict that spiders may employ varied flower-visiting strategies throughout their developmental stages, where the increasing predation risk leads to a decreased presence of spiders on flowers as they mature during ontogeny. [ABSTRACT FROM AUTHOR]

Two species assigned to Massuria Thorell, 1887 are reviewed. The female of Massuria bandian Tang & Li, 2010 is described for the first time from Jianfengling National Natural Reserve, Hainan Province, China. The species Diaea simplex Xu, Han & Li, 2008 is described as a synonym of Massuria bellula Xu, Han & Li, 2008 based on female and male specimens from Guangdong Province, China. Massuria min sp. nov. described as a new species (female, Fujian Province, China). Detailed illustrations and a distribution map are provided for these three species of Massuria. [ABSTRACT FROM AUTHOR]

The thomisid spider Synema globosum (Fabricius, 1775) is widely distributed in the Palaearctic realm and is particularly common in southern parts of zones with a temperate climate. Seven subspecies have been described; the widely distributed nominotypical subspecies, S. g. globosum and six with much more restricted ranges. As of now, just two subspecies are still recognised as valid while the others have been synonymized with the nominate subspecies. This study now revalidates S. g. canariense Dahl, 1907 (subsp. reval.) based on findings from molecular and comparative morphological analysis. We also argue that the synonymization of the subspecies S. g. daghestanicum Utochkin, 1960 and the species S. japonicum Karsch, 1879 with S. globosum in Ono (1988) is formally correct, but needs further investigation with modern methods. [ABSTRACT FROM AUTHOR]

We describe a new species of giant crab spider of the genus Sadala Simon, 1880 collected in Lowland Evergreen rainforests at the Tiputini Biodiversity Station, Yasuni Biosphere Reserve, Amazonian Ecuador. This new species corresponds to the first record of the genus from Ecuador. Females of the new species of Sadala are similar to S. punicea and S. nanay, by having the epigyne with a median septum diamond‐shaped posteriorly. The new species is easily distinguished from S. punicea and S. nanay by having relatively straight anterior lateral margins of the median septum. This study increases to 10 the number of described species of Sadala. [ABSTRACT FROM AUTHOR]

Spiders have become a model group for sexual selection and mating system studies, but our understanding of courtship behavior in the group is heavily biased towards the infraorder Araneomorphae ('modern' spiders, such as orb weavers, jumping spiders, wolf spiders, crab spiders and many more). In the Mygalomorphae (tarantulas, trapdoor spiders, funnel‐web spiders and relatives), only a few descriptions of courtship are available and recent developments in the phylogenetics of the group offer an opportunity to remap and investigate the evolution of mating behaviors. Using 81 trials filmed in captivity, we report on the courtship behaviors of the iconic Sydney funnel‐web spider (Atracidae: Atrax robustus), which belongs to a large clade of biologically understudied mygalomorphs. Thirteen distinct behaviors are described for males, out of which at least two seem new to mygalomorphs, while four female behaviors are described. Moreover, the sequences of male behaviors are presented for when they come into contact with females inside or outside of their burrows. The mating positions of the pair, including details of how males use their legs and clasping spurs to grasp the females, are also presented. We discuss our results in a modern phylogenetic context, filling a gap in the understanding of sexual selection in the Mygalomorphae where such studies are rare and biased towards tarantulas. Finally, we attempt to consolidate descriptions of potentially homologous behaviors from several families in the group and offer insights into the evolution of cannibalism, male clasping spurs and female catalepsis (quiescence while mating). [ABSTRACT FROM AUTHOR]

In Europe, the meadow spittlebug Philaenus spumarius (L.) (Hemiptera Aphrophoridae) is the main vector of the bacterium Xylella fastidiosa Wells et al., the etiological agent of the Olive Quick Decline Syndrome. The froth produced by spittlebug nymphs has a primary function in protecting the insect from dehydration and thermal stress. It is also accepted that the froth protects nymphs from predators, although the underlying mechanism is not completely clear. We investigated such a process using the crab spider Synema globosum (F.) and the ant Crematogaster scutellaris (Olivier) as model species. Nymphs of P. spumarius were divided into two groups, one whose froth was left and one whose froth was removed. The nymphs were then exposed to predators and their survival recorded. The survival of defrothed nymphs was considerably lower than controls with both spiders and ants, though this could be due to increased motility of defrothed nymphs. Moreover, to test the chemical properties of the froth and exclude any physical hindrance effect, P. spumarius nymphs and dead Sarcophaga carnaria (L.) larvae (maggots) under three different conditions (defrothed, water-coated, and centrifuged froth-coated) were offered to workers of C. scutellaris. The survival of the nymphs and ants' bites to both preys were recorded. Again, defrothed nymphs showed a lower survival probability compared to those moistened with water and froth, while no differences were found between these two treatments, suggesting a chemical deterrence or mimicry of the froth. The highest number of ants' bites towards nymphs and maggots was recorded in the defrothed group, while the lowest in the froth-coated nymphs. A significant difference between the water- and froth-coated treatments was only found in nymphs and not in maggots, suggesting the presence of some residual substances on the nymph's integument that could have a deterrent or masking effect. Additionally, our direct observations of ants drinking the froth reinforce chemical mimicry as a more plausible explanation than deterrence. In conclusion, our findings suggest that the froth plays an antipredatory role, at least for predators that use mainly olfactory cues to localise their preys, through a chemical mimicry mechanism. [ABSTRACT FROM AUTHOR]

Two new species of crab spider are described from the Xiaolong Mountains in Gansu Province, China: Ebelingia spirala sp. nov. (♂♀) and Lysiteles longensis sp. nov. (♂♀). Detailed morphological characters, a distribution map, photographs, and illustrations of the habitus and copulatory organs are given for each species. [ABSTRACT FROM AUTHOR]

They mostly come at night: Predation on sleeping insects by introduced candy-striped spiders in North America We rarely observed candy-striped spiders invading other spiders' webs to engage in kleptoparasitism or araneophagy. gl In North America, candy-striped spiders often occur in very high densities (e.g., Tomascik, [13]), and they thrive in a variety of habitats, suggesting that they may have strong impacts on insect communities. Keywords: Enoplognatha latimana; Enoplognatha ovata; foraging ecology; insect sleep; natural history; predation behavior EN Enoplognatha latimana Enoplognatha ovata foraging ecology insect sleep natural history predation behavior 1 6 6 05/03/23 20230501 NES 230501 Candy-striped spiders (two closely related and nearly indistinguishable species: I Enoplognatha ovata i (Clerck, 1757) and I Enoplognatha latimana i Hippa & Oksala, [8]) are, at first glance, unremarkable cobweb weavers in the family Theridiidae. We have also observed candy-striped spiders invading the webs of other spiders to steal prey, consume the host spiders, and/or take over the web and hunt on it (Figure 2c,d, Appendix S1: Table S2). [Extracted from the article]

This short paper reports a thomisid species which is new for the Turkish araneofauna. The characteristic features and photographs of Ozyptila rigida (O. Pickard-Cambridge, 1872) are presented in addition to its distribution map. [ABSTRACT FROM AUTHOR]

Understanding the complex interplay of factors shaping polymorphic changes within individuals represents a longstanding conundrum in biology. Some crab spiders (Thomisidae) are examples of sit-and-wait predators that can change their body coloration. Many factors may influence crab spider color polymorphism with multiple explanations receiving various levels of support. Here we examined the daytime and nighttime activities and predator and prey interactions for two yellow-white polymorphic crab spiders, Thomisus labefactus and Ebrechtella tricuspidatus in the field. We thereupon conducted a manipulative experiment using dummies with color morphs visibly resembling the spiders when placed on background-matched flowers. We measured the spectra reflected from the dummies and their floral backgrounds and used insect visual models to determine if they are likely to be visible to a range of insects by night and day. We found that both color morphs of each species were more active by night than by day. Our visual models revealed that the spider's bodies were unlikely to be cryptic. Together, these results suggest that the crab spiders might exploit flower colorations during the night but not during the day. They also indicated that explanations of why crab spiders utilize certain color polymorphs are context dependent and will vary with time, and whether predators, prey, or both, are present. Significance statement: Crab spiders are an excellent model for investigating a long-standing challenge in evolutionary biology: understanding the causes and consequences of polymorphic coloration in animals. Studies have postulated a range of explanations with some support for each. Broader studies encompassing all interactions between spiders and their predators and prey across the day and night are urgently needed. Here we combined an around-the-clock spider activity survey with field experiments and insect visual models to show that the types of interactions between spider color morphs and their predators and prey differ over the day and night. Our study suggests that outcomes of experiments examining the adaptive drivers of polymorphisms may be dependent upon the context within which the observations were made, and that examining interactions across temporal contexts is required to fully uncover the various drivers of the polymorphisms. [ABSTRACT FROM AUTHOR]

Biota Fapesp (IBSP 138314), Florianópolis, Costão do Santinho, Morro das Aranhas, 1 , 2007, F. Albertoni (IBSP 144188); B São Paulo: b Mogi das Cruzes, PNM Serra do Itapety, 23 29 S, 46 12 W, 23.4833°S, 46.2°W, 1 , 13-19.x.2003, Eq. & Souza, C.A.R. (IBSP 038507), Primavera, Porto Primavera, 1 , 23.ii.2001, Candiani, D. F. & Indicatti, R. P. (IBSP 039339B), Primavera, UHE Sérgio Motta, 1 , i-ii.2000, Equipe BIOTA (IBSP 029650), 5 , 15 , 1J, i-ii.2000, Equipe BIOTA (IBSP 029738A), 6 , 17 , i-ii.2000, Equipe BIOTA (IBSP 029860A), 6 , 13 , i-ii.2000, Equipe BIOTA (IBSP 029873A), 1 , i-ii.2000, Equipe BIOTA (IBSP 029881A), 4 , 4 , i-ii/2000, Equipe IBSP (IBSP 029897), Rosana, UHE Rosana, 2 , 2 , 3J, xii.1986, Equipe IBSP (IBSP 004463), São Paulo, 1 , 1 , [no date], Cunha, F.S. [Extracted from the article]

Synema Simon, 1864 is a relatively large genus of family Thomisidae Sundevall, 1833 and currently includes 124 species distributed worldwide, except for the Polar Regions. However, Synema can be regarded as being poorly represented in China, with only seven species, three of which are endemic.A new spider species of the genus Synema from Guiyang City in China, is described under the name of S. guiyang J. Zhang, Q. Lu & H. Yu, sp. nov. Detailed descriptions and photographs of the new species are provided. DNA barcodes (a partial fragment of the mitochondrial cytochrome oxidase subunit I gene, COI) of the species were obtained to confirm matching of the sexes and for future use in molecular studies.

Background: Among the 16 Neotropical genera of Philodromidae, Cleocnemis has the most troublesome taxonomic situation. Remarkable morphological differences among several genera historically said to be related to Cleocnemis denote controversial notions and general uncertainty about the genus identity. Thus, to clarify the genus limits and contribute to the understanding of Neotropical Philodromidae, we conducted a morphological analysis, along with Bayesian Inference and Maximum Likelihood molecular phylogenetic analyses focusing on Cleocnemis and related genera of Thanatinae. All of the 14 species previously placed in Cleocnemis were studied, and eight of them included in the molecular analyses based on fragments of 28S rDNA, histone H3, 16S rDNA, and cytochrome oxidase I (COI). Results: Cleocnemis was recovered as polyphyletic. Most of its species are distributed into six lineages allocated into five morphologically recognizable groups: Group I [Cleocnemis heteropoda], representing Cleocnemis sensu stricto and two new junior synonyms, Berlandiella and Metacleocnemis; Group II [Tibelloides bryantaecomb. nov., Tibelloides punctulatuscomb. nov., Tibelloides reimoserinom. nov., and Tibelloides taquaraecomb. nov.], representing Tibelloidesgen. rev., which was not recovered as monophyletic; Group III [Fageia moschatacomb. nov., Fageia roseacomb. nov.], representing the genus Fageia; Group IV ["Cleocnemis" lanceolata]; and Group V ["Cleocnemis" mutilata, "Cleocnemis" serrana, and "Cleocnemis" xenotypa]. Species of the latter two groups are considered incertae sedis. Cleocnemis spinosa is maintained in Cleocnemis, but considered a nomen dubium. Cleocnemis nigra is considered both nomen dubium and incertae sedis. We provide a redelimitation of Cleocnemis, redescription, neotype designation, and synonymy of type-species C. heteropoda. Taxonomic notes on composition, diagnosis, and distribution for each cited genus are also provided. Phylogenetic results support the division of Philodromidae into Thanatinae new stat. and Philodrominae new stat. and suggest expansion of their current compositions. Terminology of genital structures of Philodromidae is discussed. Conclusions: Our results bring light to Cleocnemis taxonomy and enhance the understanding of the relationships within Philodromidae, especially through the assessment of neglected Neotropical taxa. [ABSTRACT FROM AUTHOR]

Epigaeic (ground‐active) spiders are dominant predators of arthropods and are important prey for vertebrates in sagebrush steppe systems. As part of the Sagebrush Steppe Treatment Evaluation Project (SageSTEP), the response of epigaeic spiders to sagebrush steppe restoration treatments was evaluated. Spiders were pitfall trapped pre‐treatment and for up to 7 years post‐treatment at 20 sites in the interior western United States. Spider species, functional groups, and communities were analyzed as regards site conditions and in response to treatments (prescribed fire, mechanical, and herbicide) designed to restore sagebrush steppe lands encroached by piñon–juniper woodlands (Pinus and Juniperus spp.) and invaded by cheatgrass (Bromus tectorum). A total of 10,149 epigaeic spiders were caught during the 8‐year sampling period (2006–2014), comprising 18 families, 51 genera, and 109 species. Ten species are currently undescribed, including two species of jumping spiders (Salticidae), two species of funnel spiders (Agelenidae), and a species of trapdoor spider (Euctenizidae). Nearly 70% of adult catch comprised the 10 most commonly collected species; 50 species were caught fewer than five times. Spiders of the family Gnaphosidae (ground spiders) dominated the collection (65% of adults), followed by wolf spiders (Lycosidae; 12%), jumping spiders (8%), and crab spiders (Thomisidae; 4%). Fewer gnaphosids were caught in plots with higher tree cover, and this pattern was reversed by tree removal. There was no significant epigaeic spider response to the broadleaf herbicide tebuthiuron, nor to mowing or clear‐cutting. Mastication caused a subtle increase in epigaeic spider richness at Utah juniper sites. Prescribed fire decreased abundance and richness of epigaeic spiders in the short term (1 year post‐treatment), with catch at most sites converging to control levels by Year 2 post‐treatment; application of the annual herbicide imazapic at treeless sites may have amplified this effect slightly in the short term. In general, gnaphosid catch and richness closely paralleled litter and bunchgrass cover. These patterns suggest that while gnaphosid spiders are not sagebrush‐obligate species per se, these spiders prefer habitat conditions that provide more hiding cover, in the form of litter and vegetation, found more often in treeless sagebrush steppe plant communities and in woodland communities that have relatively lower tree cover. [ABSTRACT FROM AUTHOR]

A fragmented landscape, which contains a patchwork of vegetated hospitable areas and a barren intervening matrix, may reduce gene flow in a population and over time result in an increase in population structure.We tested this prediction in crab spiders (Mecaphesa celer (Hentz, 1847)) inhabiting isolated habitat patches in the lava matrix of Craters of the Moon National Monument and Preserve, Idaho, USA.Using reduced‐representation genomic sequencing, we did not find evidence of population structure due to a reduction in gene flow among habitat patches.Instead, our results show strong evidence of panmixia likely due to abundant juvenile dispersal and possible connectivity to outer regions surrounding the lava flows despite the species' habitat specificity. [ABSTRACT FROM AUTHOR]

Heriaeus buffoni (Audouin, 1826) is reported for the first time from the Canary Islands, where it was found on Lanzarote. This also represents the first record of the genus in the archipelago. All individuals were collected with pitfall traps installed in nitrophilous synanthropic shrub vegetation near urban areas. Species identification was based on male genitalia only as females were not sampled. A map including all known records from Lanzarote, drawings of the pedipalps and photographs of living and preserved specimens are presented. [ABSTRACT FROM AUTHOR]

In aggressive mimicry, a predator accesses prey by mimicking the appearance and/or behavior of a harmless or beneficial model in order to avoid being correctly identified by its prey. The crab spider genus Phrynarachne is often cited as a textbook example of masquerading as bird droppings (BDs) in order to avoid predation. However, Phrynarachne spiders may also aggressively mimic BDs in order to deceive potential prey. To date, there is no experimental evidence to support aggressive mimicry in masquerading crab spiders; therefore, we performed a field survey, a manipulative field experiment, and visual modeling to test this hypothesis using Phrynarachne ceylonica. We compared prey-attraction rates among BDs, spiders, and control empty leaves in the field. We found that although all prey combined and agromyzid dipterans, in particular, were attracted to BDs at a higher rate than to spiders, other dipterans and hymenopterans were attracted to BDs at a similar rate as to spiders. Both spiders and BDs attracted insects at a significantly higher rate than did control leaves. As predicted, prey was attracted to experimentally blackened or whitened spiders significantly less frequently than to unmanipulated spiders. Finally, visual modeling suggested that spiders and BDs can be detected by dipterans and hymenopterans against background leaves, but they are indistinguishable from each other. Taken together, our results suggest that insects lured by spiders may misidentify them as BDs, and bird-dropping masquerading may serve as aggressive mimicry in addition to predator avoidance in P. ceylonica. [ABSTRACT FROM AUTHOR]

Philodromus poecilus (Thorell, 1872) is a Transeurasian species reported from most parts of Europe except the British Isles and the Iberian Peninsula. Although widely distributed, this species is extremely rarely recorded in Germany and neighbouring countries. In Bavaria, it has not been found since the time of Ludwig Koch (1825-1908). Recently, several specimens were collected from urban plane trees in Deggendorf (Lower Bavaria), proving that the species is still present in Bavaria. Additionally, images of the copulatory organs and of living and preserved specimens are presented, as is a compilation of records in Germany and neighbouring countries. [ABSTRACT FROM AUTHOR]

A list of 34 thomisid species belonging to 21 genera collected in Jangxi Province of China is provided. Five new species are described: Angaeus xieluae Liu, sp. nov. (♂♀), Lysiteles subspirellus Liu, sp. nov. (♀), Oxytate mucunica Liu, sp. nov. (♀), Pharta lingxiufengica Liu, sp. nov. (♀), Stephanopis xiangzhouica Liu, sp. nov. (♀). A new combination is proposed: Ebelingia forcipata (Song & Zhu, 1993) comb. nov. (ex. Ebrechtella Dahl, 1907). Previously unknown females of E. forcipata (Song & Zhu, 1993), Oxytate bicornis Liu, Liu & Xu, 2017, and Xysticus lesserti Schenkel, 1963 are described for the first time. Stephanopis O Pickard-Cambridge, 1869, a genus previously known from Australasia and South America, is recorded from the Asian mainland for the first time. [ABSTRACT FROM AUTHOR]

Selection imposed by visually hunting predators has driven the evolution of colour‐based antipredator defence strategies such as crypsis, masquerade, mimicry and aposematism. Individuals of many animals are generally considered to rely on a single type of defence strategy, but individuals of some species use multiple colour‐based defences. Many animals switch between colour‐based defences against visually hunting predators during ontogeny. However, why this occurs remains poorly understood.The crab spider Phrynarachne ceylonica is an often‐cited example of a bird dropping masquerade. It has recently been demonstrated that P. ceylonica crab spiders gain protection from their predators by being misidentified as bird droppings by their predators. P. ceylonica females show an ontogenetic shift in colour defences: early instars possess a dark and cryptic form, while at later instars and as adults, the spiders resemble bird droppings. We hypothesised that this shift may be driven by differential changes in predation risk of two defence strategies with increasing body size due to ontogeny.We tested this hypothesis by presenting naïve domestic chicks with 3D printed artificial spiders of two different sizes (small, large) and two colours (dark, bird dropping‐like), and determined whether larger bird dropping‐like spiders are more readily found and attacked than cryptic forms by chicks. We found that small cryptic spiders were more difficult to detect than small bird dropping masquerading spiders, but large cryptic spiders were attacked much more quickly and more frequently than large bird dropping masquerading spiders.Increasing predation pressure on larger, cryptic spiders during ontogeny suggests that switching to bird dropping masquerade may be a more effective defence as spiders increase in size. We thus conclude that the ontogenetic shift from crypsis to masquerade is adaptive. [ABSTRACT FROM AUTHOR]

Grassland insect pollinators have undergone population declines due to habitat loss and degradation. Patch-burning is a management method used to reduce woody plant encroachment and maintain grassland habitats. However, the impacts of fire on the quality and quantity of floral resources (nectar volume, total sugar, and sucrose concentration) available to insect pollinators are understudied. Evaluating how time since last fire and season of fire impact nectar quality and quantity is vital to understanding the overall impact of fire on insect pollinator communities. For this study, 10 flowering forb species (Asclepias viridis, Baptisia alba, Cirsium undulatum, Desmodium canadense, Monarda citriodora, Monarda fistulosa, Oenothera speciosa, Penstemon tubaeflorus, Ruellia humilis, Spiranthes cernua) were selected in The Nature Conservancy's Joseph H. William's Tallgrass Prairie Preserve in an area managed with patch-burning and cattle grazing. Study sites were burned in spring 2018, summer 2018, summer 2019, and spring 2020, with three replicates of each treatment (for 12 total burn units). In each unit, we collected nectar from flowering individuals of each plant species with microcapillary tubes to measure standing crop or the nectar in flowers at any given time that is available to insect pollinators. Total volume of nectar and sucrose concentration were recorded, and total mg of sugar was calculated. Desmodium canadense flowering individuals were only located in units burned the previous spring, whereas P. tubaeflorus flowering individuals were only located in units burned the previous summer. For the eight remaining species, total volume of nectar, total mg of sugar, and sucrose concentration varied with different burn regimens for different species. Cirsium undulatum inflorescences with crab spiders (Thomisidae) had higher volumes of nectar and higher amounts of sugar available. This study highlights how a patch-burn approach with different fire return intervals may benefit insect pollinators at the community level by providing a wide range of nectar qualities and quantities to support insect pollinators with different nutritional needs. [ABSTRACT FROM AUTHOR]

We report the first records of the poorly known crab spider Tmarus longicaudatusMillot, 1942 in Mauritania, Namibia and the United Arab Emirates (UAE). The new record in Mauritania extends the distribution of the species by almost 2750 km to the west from the closest and type locality in Niger. The new record in Namibia is 1000 km north of the closest locality in South Africa. New records in the UAE are more than 900 km east of the closest locality in central Saudi Arabia. Using all available records, we present the known distribution of the species and its climate-based predicted range, indicating a wide distribution in arid to semi-arid regions. Considering its wide expected distribution, extending throughout Africa and the Arabian Peninsula, integrative taxonomic studies are needed to clarify the species status of this masquerading spider. [ABSTRACT FROM AUTHOR]

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Establishing species boundaries is one of the challenges taxonomists around the world have been tackling for centuries. The relation between intraspecific and interspecific variability is still under discussion and in many taxa it remains understudied. Here the hypothesis of single versus multiple species of the crab spider Synema globosum (Fabricius) is tested. The wide distribution range as well as its high morphological variability makes this species an interesting candidate for re-evaluation using an integrative approach. This study combines information from barcoding, phylogenetic reconstruction based on mitochondrial CO1 and ITS2 of more than 60 specimens collected over a wide range of European localities, and morphology. The findings show deep clades with up to 6% mean pairwise distance in the CO1 barcode without any biogeographical pattern. The nuclear ITS2 gene did not support the CO1 clades. Morphological assessment of somatic and genital characters in males and females and a morphometric analysis of the male palp uncovered high intraspecific variation that does not match the CO1 or ITS2 phylogenies or biogeography either. Screening for endosymbiotic Wolbachia bacteria was conducted and only a single infected specimen was found. Several scenarios might explain these inconsistent patterns. While the deep divergences in the barcoding marker might suggest cryptic or ongoing speciation or geographical isolation in the past, the lack of congruent variation in the nuclear ITS2 gene or the studied morphological character systems, especially the male palp, indicates that S. globosum might simply be highly polymorphic both in terms of its mtDNA and morphology. Therefore, more data on ecology and behaviour and full genome sequences are necessary to ultimately resolve this taxonomically intriguing case. [ABSTRACT FROM AUTHOR]

The Iraqi spider fauna includes several dozens of species described and reported mostly by local researchers but still there are considerable sampling gaps. For the first time in Iraq, Agelena orientalis C. L. Koch 1837 (Agelenidae), Oxyopes globifer Simon, 1876 (Oxyopidae), and Thanatus formicinus (Clerck, 1757) (Philodromidae) are recorded. In addition, newly collected material of Bassaniodes tristrami (O. Pickard-Cambridge, 1872) (Thomisidae) and Eusparassus mesopotamicus Moradmand & Jäger, 2012 (Sparassidae) are also presented. The characteristic features, habitus and copulatory organs of all species are presented here along with their geographic distribution. [ABSTRACT FROM AUTHOR]